Risk Assessment Toolbox. Risk Analysis Training

Transcription

1 Risk Assessment Toolbox Risk Analysis Training

2 Risk Profiles in Codex PURPOSE: The risk profile is an abbreviated discussion paper that lays out the key elements of a MRM concern in order to facilitate decision-making on the part of the risk manager in relation to the need and scope of newly proposed work SCOPE AND RATIONALE: Identify the food safety issue (microbial hazard & commodity of concern) and provide information required by the risk manager to make an informed decision on the need to undertake work on the subject

3 Codex Committee on Food Hygiene Risk Profile Elements 1. Hazard-food commodity combination(s) of concern 2. Description of the public health problem 3. Food production, processing, distribution and consumption 4. Available options for control 5. Additional factors (e.g., consumer perceptions, economics, fair trade issues) 6. Risk assessment needs and questions for the risk assessors 7. Available information and major knowledge gaps

4 Risk Profile Can be viewed as a qualitative risk assessment combined with a qualitative control options assessment Often an early step in risk analysis process used to develop hazard analysis

5 Risk Assessments Tools Risk Assessment * Science based Risk Management * Policy based Risk Communication * Interactive exchange of information and opinions concerning risks

6 Food Safety Risk Assessments There is a variety of different types of risk assessments Need the right tool for the right job Chemical safety and risk assessment Food/color additives Pesticide residue risk assessment Animal drug residues Process safety Microbiological risk assessment Biological hazards risk assessments Allergens Nutrition Naturally occurring toxins Food Defense Biotechnology Genetically modified foods Pest risk assessment plant and animal

7 Methodology Qualitative Narrative, categorical (rating) or graded (ranking) nonnumerical risk estimates Semi-quantitative Narrative or categorical rankings converted into quantitative values for the purpose of further analysis Validity of normal values can be questionable Quantitative Numerical estimates of risk Deterministic Probabilistic/Stochastic

8 Qualitative RA Compiles, combines and presents evidence to support a non-numerical estimate and description of a risk. Theory, data, time or expertise are limited Routine non-controversial tasks To assure consistency and transparency in handling risk For big broadly defined problems where quantitative risk assessment is impractical When risk management needs can be met qualitatively May be used in conjunction with a risk profile

9 Quantitative RA Numerical expressions of risk Generally more informative than qualitative estimate Preferred when data and resources are available Comes in two forms: Deterministic or probabilistic Generally considered more resource/data intensive than qualitative risk assessment

10 Assessing Food Safety Risks The product of a quantitative risk assessment is a mathematical statement based on cumulative probabilities of certain events happening or the chance of harm following exposure to a biological agent capable of causing harm

11 Consider Variability and Uncertainty In deterministic quantitative risk assessments we pick a single point in the distribution of key variables Mean 95% point Selection of assumed value can greatly influence results < Home Refrigerator Temperatures ( F)

12 The World Is a Very Diverse Place

13 The World Is a Very Diverse Place

14 The World Is a Very Diverse Place

15 Uncertainty vs. Variability Uncertainty Incomplete information Can reduce by acquiring more information Variability Inherent diversity of a system Cannot be reduce by acquiring more information though may achieve a better estimate

16 Consider Variability and Uncertainty Try not to use single point values Instead try to use probablistic models which use distributions that capture variability and uncertainty Capture via simulation modeling < Home Refrigerator Temperatures ( F)

17 Probabilistic Modeling Use Monte Carlo simulations to increase the accuracy of the predictions Considers parameters as distributions instead of single values Risk managers often have trouble with probabilistic models because do not get a binary answer Puts the responsibility for risk decisions clearly on the risk manager

18 Monte Carlo Simulation What number would I get if I rolled three dice?

19 Dealing with Distributions = 7

20 Dealing with Distributions = 15

21 Monte Carlo Simulation Frequency Mean = 10.5 Sum

22 Incorporating Diversity into Availability of user friendly software has greatly changed the ability to describe variability and uncertainty Evaluations

23 Food Safety Risk Assessments There is a variety of different types of risk assessments Need the right tool for the right job Chemical safety and risk assessment Food/color additives Pesticide residue risk assessment Animal drug residues Process safety Microbiological risk assessment Biological hazards risk assessments Allergens Nutrition Naturally occurring toxins Food Defense Biotechnology Genetically modified foods Pest risk assessment plant and animal

24 Food Safety Risk Assessments Within a risk assessment class there can be multiple forms of risk assessment; e.g. microbial risk assessments Product/Pathogen Pathway Risk Ranking Risk/Benefit Analysis Risk/Risk Analysis Geographical Introduction Analysis Consequence Analysis

25 Risk Assessment Tool 1: Hazard/Product Pathway Analysis: Example -Cold Smoked Salmon and Listeria monocytogenes

26 Hazard/Product Pathway Analysis Used in determining what are the factors along the farm to table continuum that contribute to the risk associated with a specific hazard Used to Design food safety system to achieve risk mitigations Develop risk-based standards Establish monitoring and verification programs

27 Catch and transport Frozen Storage Thaw Refrigerated Storage Rinse Dehead/Gut/Split Rack/Equilibrate Hot Smoke Cold Smoke Refrigerated Storage Slice/Mince/Mix Drain Brine Dry Salt Rinse Air/MAP Package Market Distribution Frozen Storage Refrigerated Storage

28 Data Needs for Exposure Assessment Phase I: Production Through Sale Frequency and extent of contamination in raw materials and finished product, and at intermediate steps if possible Growth/survival characteristics of pathogen Product composition and characteristics Storage times and temperatures Impact of various processing steps

29 Data Needs for Exposure Assessment Phase II: Sale Through Consumption How food is consumed Storage times and temperatures Potential contamination in home Impact of preparation steps and practices

30 Data Needs for Exposure Assessment Phase III: Consumption information Serving size Number of servings consumed Differences in consumption based on Age Ethnicity Seasonality Geography

31 Risk Characterization A: Home Storage Time B: Home Storage Temperature C: Retail Storage Time D: Initial Level E: Number of Portions Contaminated in High Hygiene Plants F: Temperature During Distribution

32 RA Tool 2: Risk Ranking

33 Managing Food Safety Risk Full table of hazards and risks Trying to do everything means nothing gets done well Regulatory agencies and industry are both finding that they need more objective tools for priority setting

34 Risk Ranking Used in U.S. for over 25 years for priority setting priority setting for environmental hazards Largely done as qualitative or semi-quantitative risk profiles Often confused risk management and risk assessment got a tarnished reputation as a result Separation of risk assessment and risk management and emergence of quantitative approaches have rekindled interest

35 Predicted Cases of Listeriosis per Annum for Total Population 4.00 Total Cases Listeriosis per Annum (log scale) DM PM HFD FNR SUC P UM CR SS F FR V DFS FSC SSC SRC DS RS PF IC PC CD HC

36 Predicted Cases of Listeriosis per Serving for Total Population DM FNR P UM SS CR HFD SUC PM FSC FR PF RS F DFS SSC SRC V DS IC PC CD HC Total Cases Listeriosis per Serving (log scale)

37 Decreased Risk per Annum Clusters A and B Clusters C and D Cluster E Very High Risk Deli Meats Frankfurters (not reheated) High Risk Pâté and Meat Spreads Unpasteurized Fluid Milk Smoked Seafood Moderate Risk No food categories Cluster 1 Decreased Risk per Serving High Risk High Fat and Other Dairy Products Pasteurized Fluid Milk Soft Unripened Cheese Moderate Risk No food categories Moderate Risk Cooked RTE Crustaceans Moderate Risk Deli-type Salads Dry/Semi-dry Fermented Sausages Frankfurters (reheated) Fresh Soft Cheese Fruits Semi-soft Cheese Soft Ripened Cheese Vegetables Moderate Risk No food categories Cluster 2 Low Risk Preserved Fish Raw Seafood Cluster 3 Moderate Risk No food categories Low Risk No food categories Very Low Risk Cultured Milk Products Hard Cheese Ice Cream and Other Frozen Dairy Products Processed Cheese Cluster 4

38 Risk Ranking Can span the entire qualitative to quantitative spectrum with all the benefits and limitations of each Complexity increases with number of: Classes of agents (e.g., chemical, microbiological) Agents within a class Biological end points associated with an agent Food classes Diversity of foods within a class Diversity in susceptibility of population

39 Risk Ranking Risk Assessments Six levels based on increasing complexity Level 1: Single agent in multiple food classes Level 2: Single class of agents in a single food class Level 3: Single class of agents in multiple food classes Level 4: Multiple classes of agents in a single food Level 5: Multiple classes of agents in a single food class Level 6: Multiple classes of agents in multiple classes of foods

40 Risk Ranking Future success in advancing risk ranking techniques beyond level 2 is going to be highly dependent on finding a common metric that is reasonable, understandable to the public, and easy to use DALY s, pseudo-daly s

41 Development of Common Metrics Increasingly using Disability Adjusted Life Years for consideration of comparative risks Based on concept that there is an ideal state from which you subtract

42 Risk Ranking Assessment Seeing similar comparative assessments and tools being applied to quantitative risk ranking assessment Recent development and release of the FDA irisk software for doing comparative risk assessment tool makes it increasingly possible to do risk-risk evaluations

43 RA Tool 3: Risk Benefit Analysis

44 Risk Benefit Assessment There has been renewed interest in consideration of benefits in food safety decision making for chemicals similar to what is done for the approval of new drugs, biologics and medical devices The major argument for risk-benefit is that this would allow more informed decisions by putting risks in a broader societal context

45 Risk Benefit Assessment A number of things that are likely to get in the way of that goal A long history of safety only consideration for premarket approvals for foods Consumers risk tolerance is much less for foods than drugs Difficult to communicate how consumer benefit Why consider tolerances when there is surplus production of most foods high avoidability Changing somewhat due to consideration of food security issues Difficult to document and quantify benefits and then compare against risks

46 Always Remember A risk assessment does not provide THE ANSWER It provides information that the risk managers can draw upon to make more informed decisions